Electronic components generate heat while they are used and the removal of this heat is necessary to prevent thermal destruction of the component and improve operating efficiency. For microelectronic components such as integrated circuits, thermally conductive materials such as thermally conductive greases, gels, or adhesives are provided to help remove heat from the component.
In general, microelectronic devices comprise integrated circuits protected within a housing or packaging, and a thermally conductive material applied so as to contact directly with both the integrated circuit element and the external packaging or a heat sink if one is provided. The heat generated from the integrated circuit chips during operation is transmitted through the thermally conductive material away from the device, and further radiated therefrom. 
For example, U.S. Pat. No. 6,255,257 entitled “SILICONE GREASE COMPOSITION” relates to a silicone grease composition having high thermal conductivity, comprising (A) 50 to 95 weight percent of a mixture of an aluminum nitride powder having an average particle size of 0.5 to 5 microns and an aluminum nitride powder having an average particle size of 6 to 20 microns, (B) 5 to 15 weight percent of organopolysiloxanes having a viscosity of from 50 to 50,000 cs at 25° C. and (C) 0 to 35 weight percent of at least one inorganic compound powder having an average particle size of 0.5 to 100 microns selected from the group consisting of zinc oxide, alumina, boron nitride and silicon carbide powders.
These prior art systems are somewhat limited in that the thermal conductivity of the material is most closely related to the amount of thermally conductive filler in the material. As more filler material is added, the thermal conductivity increases. Unfortunately, as more filler is added, the viscosity of the resulting material also increases. The balance between achieving a high thermal conductivity through high filler loading while maintaining a workable viscosity is often an undesirable trade-off. Many of these materials are dispensed with a syringe and therefore the viscosity must remain low enough to allow flow through a needle.
It is therefore commercially desirable to provide a material with a high filler loading while maintaining a working viscosity. It would further be desirable to provide a highly filled, low viscosity thermally conductive material which is needle dispensable.